The invention relates to medication injecting device assemblies and specifically to a patient-fillable ampule for use with a hypodermic injection device which injects medication but which does not require piercing the skin of a patient with a hypodermic needle.
The ampule of the invention described herein is a patient-fillable ampule which may be used by patients with suitable medication wherein the ampule is to be filled by the patient prior to administering the medication. The patient-fillable ampule may be used on a one time only basis or may be used for multiple injections. Additionally, the ampule may be used as a conventional syringe.
Although many forms of syringes are known, the ampule, or syringe of the invention is particularly adapted for use with a powered non-invasive hypodermic injection device wherein the medication is injected through the skin of the patient without the need for piercing the patient's skin with a hypodermic needle. As such, the ampule is subject to extremely high pressures, on the order of 8000 psi, and must therefore be structurally sound to withstand such pressures.
Powered hypodermic devices are known which provide one or multiple gas charges to delivery injection by non-invasive hypodermic means. Generally, the smaller powered hypodermic devices which are intended for use by patient's self-administering medication are one-shot devices, in that a new, gas-filled cartridge must be provided for each injection. Larger devices are known which provide multiple injections from a single gas charge but these devices are generally quite large and too expensive for self-administration of medication. It is particularly important that patients who self-administered medication know how many times the device has been used on a given charge, so that the patient will not attempt to administer medication when the device does not have sufficient gas charge therein to provide a complete injection of the medication.
An object of the invention is to provide a patient-fillable ampule for a powered-hypodermic injection device which will be suitable to withstand the extreme pressures generated by such a device.
Another object of the invention is to provide a powered hypodermic injection device which is capable of providing multiple injections.
A further object of the invention is to provide an ampule for a powered-hypodermic injection device which may be used to provide a non-invasive injection and which may also be used as a conventional, invasive syringe.
Still another object of the invention is to provide such a device which includes means for indicating the number of injections administered on a particular gas charge.